US6756155B1 - Positive active material for rechargeable lithium batteries and method of preparing same - Google Patents

Positive active material for rechargeable lithium batteries and method of preparing same Download PDF

Info

Publication number
US6756155B1
US6756155B1 US09/505,389 US50538900A US6756155B1 US 6756155 B1 US6756155 B1 US 6756155B1 US 50538900 A US50538900 A US 50538900A US 6756155 B1 US6756155 B1 US 6756155B1
Authority
US
United States
Prior art keywords
active material
group
powder
licoo
positive active
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US09/505,389
Inventor
Ho-jin Kweon
Seung-Kee Kim
Sang-Moon Hwang
Young-Bae Roh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Samsung SDI Co Ltd
Original Assignee
Samsung SDI Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=36797643&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US6756155(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Samsung SDI Co Ltd filed Critical Samsung SDI Co Ltd
Assigned to SAMSUNG SDI CO., LTD. reassignment SAMSUNG SDI CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HWANG, SANG-MOON, KIM, SEUNG-KEE, KWEON, HO-JIN, ROH, YOUNG-BAE
Application granted granted Critical
Publication of US6756155B1 publication Critical patent/US6756155B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G51/00—Compounds of cobalt
    • C01G51/40—Cobaltates
    • C01G51/42—Cobaltates containing alkali metals, e.g. LiCoO2
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G51/00—Compounds of cobalt
    • C01G51/40—Cobaltates
    • C01G51/42—Cobaltates containing alkali metals, e.g. LiCoO2
    • C01G51/44—Cobaltates containing alkali metals, e.g. LiCoO2 containing manganese
    • C01G51/50—Cobaltates containing alkali metals, e.g. LiCoO2 containing manganese of the type [MnO2]n-, e.g. Li(CoxMn1-x)O2, Li(MyCoxMn1-x-y)O2
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/581—Chalcogenides or intercalation compounds thereof
    • H01M4/5815—Sulfides
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C01P2002/54—Solid solutions containing elements as dopants one element only
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
    • C01P2002/88—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by thermal analysis data, e.g. TGA, DTA, DSC
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/03—Particle morphology depicted by an image obtained by SEM
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
    • C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
    • C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/32—Thermal properties
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/40—Electric properties
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/582—Halogenides
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to a positive active material for a rechargeable lithium battery and a method of preparing and, more particularly, to a positive active material for a rechargeable lithium battery, having good structural and thermal safety properties and a method of preparing the same.
  • the rechargeable lithium battery is preferred because lithium has a high standard potential as well as a low electrochemical equivalent weight.
  • Rechargeable lithium batteries employ materials into or from which lithium can be intercalated or deintercalated as positive and negative active materials.
  • Metallic lithium has been used for the negative active material in rechargeable lithium batteries.
  • lithium metal has good reactivity toward electrolyte and deposits to form a dendric layer which increases the reactivity of lithium.
  • the problem of lithium reactivity toward the electrolyte has been addressed by replacing the lithium metal with carbon-based materials. Owing to the use of the carbon-based active materials, the potential safety problem present in metallic lithium-based batteries can be prevented while achieving a relatively higher energy density as well as the reasonable shelf life.
  • a chalcogenide metal compound from or into which a lithium ion can be extracted or inserted, during a charge or discharge, is generally used for the positive active material.
  • transition metal oxide-based compounds such as LiCoO 2 , LiMn 2 O 4 , LiNiO 2 , LiNi 1-x Co x O 2 (0 ⁇ x ⁇ 1) or LiMnO 2 are generally used for positive active material.
  • LiNiO 2 has a high charge capacity, but is difficulty produced.
  • Manganese-based material such as LiMn 2 O 4 or LiMnO 2 , etc. is easiest to prepare, is less expensive than the other materials and has environmentally friendly characteristics, but has low capacities.
  • LiCoO 2 is widely used as it has an electrical conductivity of about 10 ⁇ 2 to 1 S/cm at room temperature and high battery voltage, but has poor safety characteristics during high rate charges and discharges.
  • Such composite metallic oxides are manufactured by the solid phase method.
  • the solid phase method includes the steps of mixing with a solid raw material powder and sintering this mixture.
  • Japanese Patent publication No. Hei 8-153513 discloses a method in that Ni(OH) 2 is mixed with Co(OH) 2 , or hydroxides including Ni or Co are mixed and the mixture is heat-treated, followed by the heat-treated mixture being ground and then the ground mixture sieved to produce LiNi 1-x Co x O 2 (0 ⁇ x ⁇ 1).
  • LiOH, Ni oxide and Co oxide react and the reactant is initially sintered at 400 to 580° C. and the sintered reactant is sintered a second time at 600 to 780° C. to produce a crystalline active material.
  • the resulting active material has both low structural and thermal stability, reducing the safety of the battery.
  • a positive active material for a rechargeable lithium battery including a cobalt-based compound selected from the group consisting of compounds represented by the formulas 1 to 4:
  • A is selected from O, S, F or P
  • B is selected from S, F or P
  • M is a transition metal selected from Al, Mg, Cr or Mn; Sr; or lanthanide metal selected from La or Ce, 0 ⁇ x ⁇ 1 and 0 ⁇ y ⁇ 1.
  • the compound includes secondary particles of 10 to 30 ⁇ m in size gathered with primary particles with a size of 1 to 5 ⁇ m.
  • a surface of the active material is coated with metal oxide.
  • the present invention further includes a method of preparing the positive active material.
  • a cobalt-based compound powder selected from the group consisting of formulas 1 to 4 is obtained.
  • the compound includes secondary particles of 10 to 30 ⁇ m in size and the secondary particle is gathered with primary particles with a size of 1 to 5 ⁇ m.
  • the powder of the compound is coated with a metal alkoxide solution or a metal aqueous solution to make a metallic alkoxide or metal-coated powder.
  • the coated powder then heat-treated such that the metallic alkoxide or metal-coated powder is converted into a metallic oxide-coated powder.
  • FIG. 1 is a scanning electron microscope (SEM) photograph of LiCoO 2 used in one embodiment of the present invention
  • FIG. 2 is a SEM photograph of LiCoO 2 used in Comparative Example of the present invention.
  • FIG. 3 is a graph illustrating differential scanning calorimetry (DSC) analysis results with respect to positive electrodes of one embodiment and Comparative Example of the present invention after the electrodes are charged by 4.3V;
  • FIG. 4 is a graph illustrating DSC analysis results with respect to positive electrodes of another embodiment and Comparative Example of the present invention after rechargeable cells are charged by 4.3V;
  • FIG. 5 is a graph illustrating cycle life characteristics of the rechargeable lithium cells of the another embodiment and Comparative Example of the present invention.
  • the present invention relates to a positive active material for a rechargeable lithium battery that includes a compound selected from the group consisting of compounds represented by the formulas 1 to 4:
  • A is selected from O, S, F or P
  • B is selected from S, F or P,
  • M is a transition metal selected from Al, Mg, Cr or Mn; Sr; or a lanthanide metal selected from La or Ce,
  • a surface of the active material is coated with metallic oxide.
  • the cobalt-based compound expressed by the formulas 1, 2, 3, or 4 may be obtained by the following method, or are available by commercial purchased.
  • Cobalt salts are mixed with lithium salts in a desirable equivalent ratio.
  • the cobalt salts may include cobalt hydroxide, cobalt nitrate or cobalt carbonate and the lithium salt may include lithium nitrate, lithium acetate or lithium hydroxide. LiF or NaS is additionally used in the mixing step.
  • the mixing step may be performed with a technique known in the related art, for example a mortar grinder mixing process. If the mixing step is performed with the mortar grinder mixing process, a suitable solvent is added to the mixture and the mortar grinder mixing process is performed until a solvent-free condition is reached.
  • a suitable solvent is added to the mixture and the mortar grinder mixing process is performed until a solvent-free condition is reached.
  • the resulting mixture is heat-treated to about 400 to 600° C. to produce semi-crystalline cobalt-based compound powder selected from the group consisting of formulas 1 to 4.
  • a first heat-treating step is performed at 400 to 550° C. for 1 to 5 hours and a second heat-treating is performed at 700 to 900° C. for 10 to 15 hours. If the first heat-treating step temperature is less than 400° C., cobalt salts do not completely react with lithium salts. Whereas, if the second heat-treating step temperature is less than 700° C., it is difficult to form a crystalline material.
  • the heating step is performed by increasing temperature at a rate of 1 to 5° C./min under conditions of circulating dry air. The mixture is allowed to stand at the first or second heat-treating temperature for a predetermined time and cooled. As a result, a powder of a compound selected from the group consisting of the compounds represented by the formulas 1 to 4 is obtained.
  • the powder is re-mixed at room temperature to uniformly distribute lithium salt in the powder.
  • the resulting compound powder includes secondary particles gathered with primary particles.
  • the secondary particle has a size of 10 to 30 ⁇ m and the primary particle has a size of 1 to 5 ⁇ m.
  • the cobalt-based compound powder is coated with a metallic alkoxide solution or a metallic aqueous solution.
  • the metallic alkoxide solution is formed by the reaction of an alcohol with an alkali metal of 1 to 30 wt % of the alcohol.
  • the alkali metal may be preferably selected from Mg, Al, Co, K, Na, Ca, Si, Ti or V. More preferably, the alkali metal is selected from Mg.
  • the alcohol is preferably selected from methanol or ethanol. When the alkali metal is less than 1 wt % of the alcohol, the coating effect of the metallic alkoxide solution onto the powder in not induced.
  • the metallic aqueous solution is prepared by mixing metallic oxide with water.
  • the metallic oxide may include vanadium oxides.
  • the coating method may include a sputtering technique, a chemical vapor deposition (CVD), a dip coating and other general-purpose coating techniques. Among the techniques, the dip coating may be preferably used for coating the metallic alkoxide solution onto the powder.
  • the coated powder is dried at 120° C. for about 5 hours in an oven.
  • the drying step is performed to uniformly distribute lithium salt in the powder.
  • the dried powder is heat-treated at 300 to 800° C.
  • the heating step is performed under an atmosphere where dry air or oxygen is circulating.
  • the heat-treating temperature is lower than 300° C., the metallic alkoxide solution or the metallic aqueous solution coated on the powder is not crystallized so as to prohibit the free movement of lithium ions in the active material.
  • the metallic alkoxide solution or metal aqueous solution is converted into a metallic oxide.
  • a metallic oxide-coated active material is prepared.
  • the active material is selected from the group consisting of compound represented by the formulas 1 to 4.
  • the active material includes secondary particles of 10 to 30 ⁇ m in size.
  • the secondary particle is prepared by gathering primary particles with a size of 1 to 5 ⁇ m.
  • the metallic oxide formed on the surface of the powder may be derived from a single metallic alkoxide of metal hydrate source, or from composite sources of cobalt and metallic alkoxide.
  • LiCoO 2 can be coated with an aluminum alkoxide sol and then this alkoxide-coated LiCoO 2 is heat-treated to produce a positive active material coated with composite metallic oxide of cobalt and aluminum and/or aluminum oxide.
  • the resulting mixture was initially heat-treated at 400° C. for 5 hours under an atmosphere where dry air was circulating.
  • the first heat-treated mixture was re-mixed to uniformly distribute lithium salts in the mixture.
  • the re-mixed mixture was again heat-treated at 750° C. for 12 hours by increasing temperature at a rate of 3° C./min.
  • the first and the second heat-treating temperatures were maintained for a predetermined time and then the mixture was cooled.
  • crystalline LiCoO 2 powder was obtained.
  • This LiCoO 2 powder had secondary particles with a size of about 10 ⁇ m.
  • the secondary particle was prepared by gathering primary particles with a size of 1 ⁇ m.
  • the LiCoO 2 powder was dipped into a Mg-methoxide solution for about 10 minutes and the dipped LiCoO 2 powder was separated from the solution.
  • the dipped LiCoO 2 powder was then dried at 120° C. for about 5 hours in an oven to thereby prepare a Mg-methoxide coated LiCoO 2 powder.
  • the Mg-methoxide coated LiCoO 2 powder was heat-treated at 600° C. for about 10 hours under an atmosphere where dry air was circulating to thereby prepare a Mg oxide-coated active material.
  • the active material was mixed with Super P carbon as a conductive agent, KF-1300 polyvinylidenefluoride as a binder and N-methylpyrrolidone as a solvent to prepare an active material slurry.
  • the slurry was cast into a tape shape to act as a positive electrode.
  • the positive electrode was then assembled with a lithium metal foil for a counter electrode by using a lithium salt solution for an electrolyte to thereby fabricate a coin cell-type half-cell.
  • the lithium salt solution included a 1:1 volume ratio of ethylene carbonate and dimethyl carbonate as a solvent and 1M LiPF 6 as a solute.
  • a positive electrode was prepared in the same way as in Example 1 with the exception that the Mg-methoxide coated LiCoO 2 powder was heat-treated at 700° C.
  • a coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
  • a positive electrode was prepared in the same way as in Example 1 its with the exception that LiCoO 2 powder (commercially available from Nippon Chemical under the trade name NC-10) was dipped into a Mg-methoxide solution.
  • the LiCoO 2 powder included smooth surfaced mono particles of a 10 ⁇ m size.
  • a coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
  • a positive electrode was prepared in the same way as in Comparative Example 1 with the exception that the Mg-methoxide coated LiCoO 2 powder was heat-treated at 700° C.
  • a coin-type half-cell was fabricated with the resulting positive electrode in combination with other components as described in Example 1.
  • FIG. 1 is a SEM photograph of the LiCoO 2 powder used in Examples 1 or 2
  • FIG. 2 is a SEM photograph of the LiCoO 2 powder used in Comparative Examples 1 or 2.
  • the LiCoO 2 powder used in Examples 1 or 2 included secondary particles with a size of about 10 ⁇ m. The secondary particle was gathered with primary particles with a size of 1 ⁇ m.
  • the LiCoO 2 powder used in Comparative Examples 1 or 2 had smooth surfaced mono particles with a size of 10 ⁇ m.
  • Example 1 In order to assess the stability of the cells of Example 1 and Comparative Example 1, a DSC analysis performed.
  • the DSC analysis result illustrates the thermal stability properties of the sample.
  • a structure of a positive active material is converted from LiCoO 2 to by Li 1-x Co x O 2 .
  • Li 1-x Co x O 2 active material is unstable, oxygen boned with metal (Co—O) decomposes according to increases in temperatures.
  • the decomposed oxygen may react with an electrolyte in a cell and causes the cell to explode. Accordingly, the temperature and the quantity of heat evolved when oxygen decomposed significantly effect the stability of the cell.
  • Example 1 and Comparative Example 1 were charged by 4.3V and the positive electrode was removed from the cells.
  • LiCoO 2 was converted into Li 1-x CoO 2 .
  • the DSC on the electrodes was performed and the results are shown in FIG. 3 .
  • the DSC analysis result of LiCoO 2 used in Comparative Example 1 is indicated by a parenthesized symbol A, and that of LiCoO 2 coated with Mg-oxide used in Comparative Example 1 is indicated by another symbol A600.
  • the DSC analysis result of LiCoO 2 used in Example 1 is indicated by a parenthesized symbol B, and that of LiCoO 2 coated with Mg-oxide used in Example 1 is indicated by another symbol B600.
  • the oxygen decomposition temperature of A600 is lower than A.
  • the metallic oxide-coating layer decreases the thermal stability of the LiCoO 2 powder having smooth surfaced mono particles.
  • the metallic oxide coating layer increases the thermal stability of the LiCoO 2 powder having secondary particles with a size of about 10 ⁇ m gathered with primary particles with a size of 1 ⁇ m.
  • the oxygen decomposition temperature in B600 is higher than B and the quantity of heat evolved is lower than B.
  • the DSC analysis also was performed with respect to the position electrode prepared according to Example 2 and Comparative Example 2 and the results are shown in FIG. 4 .
  • the DSC analysis result of LiCoO 2 used in Comparative Example 2 is indicated by a parenthesized symbol A, and that of LiCoO 2 coated with Mg-oxide used in Comparative Example 1 is indicated by another symbol A700.
  • the DSC analysis result of LiCoO 2 used in Example 2 is indicated by a parenthesized symbol B and that of LiCoO 2 coated with Mg-oxide used in Example 2 is indicated by another symbol B700.
  • the result also indicates that the metallic-oxide coating beneficially effects the LiCoO 2 in Example 2, as opposed to its effects on the LiCoO 2 in Comparative Example 2.
  • FIG. 5 shows cycle life characteristics of the cells according to Example 2 and Comparative Example 2.
  • the cycle life characteristic of the cell according to Example 2 is indicated by a parenthesized symbol A700 and that of the cell according to Comparative Example 2 is indicated by a parenthesized symbol B700.
  • the cycle life characteristic of the cell which is prepared by the same method in Example 2 is indicated by a parenthesized symbol A.
  • the cycle life characteristic of the cell which is prepared by the same method Comparative example 2 (except for using LiCoO 2 without the metallic-alkoxide coating operation) is indicated by a parenthesized symbol B.
  • (A700) and (B700) have better cycle life characteristics than (A) and (B).
  • (A700) has the best cycle life characteristics.
  • a positive electrode was prepared in the same way as in Example 1 with the exception that crystalline LiCoF 2 powder was prepared by mixing LiOH, Co(OH) 2 and LiF.
  • a coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described, in Example 1.
  • a positive electrode was prepared in the same way as in Example 1 with the exception that crystalline LiCoS 2 powder was prepared by mixing LiOH, Co(OH) 2 and NaS. A coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
  • Example 2 The SEM result of LiCoF 2 and LiCoS 2 used in Examples 3 and 4 respectively was similar to Example 1. Accordingly, it is presumed that the LiCoF 2 and LiCoS 2 powder have secondary particles gathered With primary particles. In addition, the DSC results of LiCoF 2 and LiCoS 2 with and without a metallic-alkoxide coating operation were similar to Example 1, thus indicating that the thermal stability is improved by the metallic-oxide coating.
  • the positive active material of the present invention has been shown to have good thermal and structural safety properties.

Abstract

Disclosed is a positive active material for a rechargeable lithium battery. The active material includes a cobalt-based compound selected from the group consisting of the compounds represented by the formulas 1 to 4. The active material has a structure of secondary particles with a size of 10 to 30 μm and the secondary particle is gathered with primary particles with a size of 1 to 5 μm. The active material includes a metallic oxide coated on the cobalt-based compound.
LiCoA2  (1)
LiCoO2-xBx  (2)
LiCo1-xMxA2  (3)
LiCo1-xMxO2-yBy  (4)
where A is selected from the group consisting of O, S, F and P,
B is selected from the group consisting of S, F and P,
M is a transition metal selected from Al, Mg, Cr or Mn; Sr; or lanthanide metal selected from La or Ce;
0<x<1 and 0<y<1.

Description

CROSS REFERENCE TO RELATED APPLICATION
This application is based on application No. 99-11043 filed in the Korean Industrial Property Office on Mar. 30, 1999, the content of which is incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a positive active material for a rechargeable lithium battery and a method of preparing and, more particularly, to a positive active material for a rechargeable lithium battery, having good structural and thermal safety properties and a method of preparing the same.
(b) Description of the Related Art
In recent years, the development of miniaturized portable electronics provoded needs for a rechargeable battery having a high capacity as well as a light weight. From the viewpoint of the capacity improvement per unit weight, the rechargeable lithium battery is preferred because lithium has a high standard potential as well as a low electrochemical equivalent weight.
Rechargeable lithium batteries employ materials into or from which lithium can be intercalated or deintercalated as positive and negative active materials.
Metallic lithium has been used for the negative active material in rechargeable lithium batteries. However, lithium metal has good reactivity toward electrolyte and deposits to form a dendric layer which increases the reactivity of lithium. The problem of lithium reactivity toward the electrolyte has been addressed by replacing the lithium metal with carbon-based materials. Owing to the use of the carbon-based active materials, the potential safety problem present in metallic lithium-based batteries can be prevented while achieving a relatively higher energy density as well as the reasonable shelf life.
A chalcogenide metal compound from or into which a lithium ion can be extracted or inserted, during a charge or discharge, is generally used for the positive active material. Alternatively, transition metal oxide-based compounds such as LiCoO2, LiMn2O4, LiNiO2, LiNi1-xCoxO2 (0<x<1) or LiMnO2 are generally used for positive active material. LiNiO2 has a high charge capacity, but is difficulty produced. Manganese-based material such as LiMn2O4 or LiMnO2, etc. is easiest to prepare, is less expensive than the other materials and has environmentally friendly characteristics, but has low capacities. LiCoO2 is widely used as it has an electrical conductivity of about 10−2 to 1 S/cm at room temperature and high battery voltage, but has poor safety characteristics during high rate charges and discharges.
Generally, such composite metallic oxides are manufactured by the solid phase method. The solid phase method includes the steps of mixing with a solid raw material powder and sintering this mixture. For example, Japanese Patent publication No. Hei 8-153513 discloses a method in that Ni(OH)2 is mixed with Co(OH)2, or hydroxides including Ni or Co are mixed and the mixture is heat-treated, followed by the heat-treated mixture being ground and then the ground mixture sieved to produce LiNi1-xCoxO2 (0<x<1). In another method, LiOH, Ni oxide and Co oxide react and the reactant is initially sintered at 400 to 580° C. and the sintered reactant is sintered a second time at 600 to 780° C. to produce a crystalline active material.
However, in such conventional methods, the resulting active material has both low structural and thermal stability, reducing the safety of the battery.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a positive active material for a rechargeable lithium battery, having excellent structural and thermal safety properties.
It is another object to provide a method of preparing the positive active material.
These and other objects may be achieved by a positive active material for a rechargeable lithium battery including a cobalt-based compound selected from the group consisting of compounds represented by the formulas 1 to 4:
LiCoA2  (1)
LiCoO2-xBx  (2)
LiCo1-xMxA2  (3)
LiCo1-xMxO2-yBy  (4)
where A is selected from O, S, F or P
B is selected from S, F or P
M is a transition metal selected from Al, Mg, Cr or Mn; Sr; or lanthanide metal selected from La or Ce, 0<x<1 and 0<y<1.
The compound includes secondary particles of 10 to 30 μm in size gathered with primary particles with a size of 1 to 5 μm. A surface of the active material is coated with metal oxide.
The present invention further includes a method of preparing the positive active material. In this method, a cobalt-based compound powder selected from the group consisting of formulas 1 to 4 is obtained. The compound includes secondary particles of 10 to 30 μm in size and the secondary particle is gathered with primary particles with a size of 1 to 5 μm. The powder of the compound is coated with a metal alkoxide solution or a metal aqueous solution to make a metallic alkoxide or metal-coated powder. The coated powder then heat-treated such that the metallic alkoxide or metal-coated powder is converted into a metallic oxide-coated powder.
DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein:
FIG. 1 is a scanning electron microscope (SEM) photograph of LiCoO2 used in one embodiment of the present invention;
FIG. 2 is a SEM photograph of LiCoO2 used in Comparative Example of the present invention;
FIG. 3 is a graph illustrating differential scanning calorimetry (DSC) analysis results with respect to positive electrodes of one embodiment and Comparative Example of the present invention after the electrodes are charged by 4.3V;
FIG. 4 is a graph illustrating DSC analysis results with respect to positive electrodes of another embodiment and Comparative Example of the present invention after rechargeable cells are charged by 4.3V; and
FIG. 5 is a graph illustrating cycle life characteristics of the rechargeable lithium cells of the another embodiment and Comparative Example of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a positive active material for a rechargeable lithium battery that includes a compound selected from the group consisting of compounds represented by the formulas 1 to 4:
LiCoA2  (1)
LiCoO2-xBx  (2)
LiCo1-xMxA2  (3)
LiCo1-xMxO2-yBy  (4)
where A is selected from O, S, F or P,
B is selected from S, F or P,
M is a transition metal selected from Al, Mg, Cr or Mn; Sr; or a lanthanide metal selected from La or Ce,
0<x<1 and 0<y 1.
A surface of the active material is coated with metallic oxide.
The cobalt-based compound expressed by the formulas 1, 2, 3, or 4 may be obtained by the following method, or are available by commercial purchased.
Cobalt salts are mixed with lithium salts in a desirable equivalent ratio. The cobalt salts may include cobalt hydroxide, cobalt nitrate or cobalt carbonate and the lithium salt may include lithium nitrate, lithium acetate or lithium hydroxide. LiF or NaS is additionally used in the mixing step.
The mixing step may be performed with a technique known in the related art, for example a mortar grinder mixing process. If the mixing step is performed with the mortar grinder mixing process, a suitable solvent is added to the mixture and the mortar grinder mixing process is performed until a solvent-free condition is reached.
The resulting mixture is heat-treated to about 400 to 600° C. to produce semi-crystalline cobalt-based compound powder selected from the group consisting of formulas 1 to 4. Alternatively, a first heat-treating step is performed at 400 to 550° C. for 1 to 5 hours and a second heat-treating is performed at 700 to 900° C. for 10 to 15 hours. If the first heat-treating step temperature is less than 400° C., cobalt salts do not completely react with lithium salts. Whereas, if the second heat-treating step temperature is less than 700° C., it is difficult to form a crystalline material. The heating step is performed by increasing temperature at a rate of 1 to 5° C./min under conditions of circulating dry air. The mixture is allowed to stand at the first or second heat-treating temperature for a predetermined time and cooled. As a result, a powder of a compound selected from the group consisting of the compounds represented by the formulas 1 to 4 is obtained.
The powder is re-mixed at room temperature to uniformly distribute lithium salt in the powder. The resulting compound powder includes secondary particles gathered with primary particles. The secondary particle has a size of 10 to 30 μm and the primary particle has a size of 1 to 5 μm.
The cobalt-based compound powder is coated with a metallic alkoxide solution or a metallic aqueous solution. The metallic alkoxide solution is formed by the reaction of an alcohol with an alkali metal of 1 to 30 wt % of the alcohol. The alkali metal may be preferably selected from Mg, Al, Co, K, Na, Ca, Si, Ti or V. More preferably, the alkali metal is selected from Mg. The alcohol is preferably selected from methanol or ethanol. When the alkali metal is less than 1 wt % of the alcohol, the coating effect of the metallic alkoxide solution onto the powder in not induced. In contrast, when the alkali metal is, more than 30 wt % of the alcohol, the coatings layer of the metallic alkoxide solution becomes undesirably thick. The metallic aqueous solution is prepared by mixing metallic oxide with water. The metallic oxide may include vanadium oxides. The coating method may include a sputtering technique, a chemical vapor deposition (CVD), a dip coating and other general-purpose coating techniques. Among the techniques, the dip coating may be preferably used for coating the metallic alkoxide solution onto the powder.
The coated powder is dried at 120° C. for about 5 hours in an oven. The drying step is performed to uniformly distribute lithium salt in the powder. Thereafter, the dried powder is heat-treated at 300 to 800° C. The heating step is performed under an atmosphere where dry air or oxygen is circulating. When the heat-treating temperature is lower than 300° C., the metallic alkoxide solution or the metallic aqueous solution coated on the powder is not crystallized so as to prohibit the free movement of lithium ions in the active material.
According to the heat-treating step, the metallic alkoxide solution or metal aqueous solution is converted into a metallic oxide. In this way, a metallic oxide-coated active material is prepared. The active material is selected from the group consisting of compound represented by the formulas 1 to 4. The active material includes secondary particles of 10 to 30 μm in size. The secondary particle is prepared by gathering primary particles with a size of 1 to 5 μm.
The metallic oxide formed on the surface of the powder may be derived from a single metallic alkoxide of metal hydrate source, or from composite sources of cobalt and metallic alkoxide. For example, LiCoO2 can be coated with an aluminum alkoxide sol and then this alkoxide-coated LiCoO2 is heat-treated to produce a positive active material coated with composite metallic oxide of cobalt and aluminum and/or aluminum oxide.
The following examples further illustrate the present invention.
EXAMPLE 1
1 M LiOH and 1 M Co(OH)2 were dissolved in distilled water. Ethanol of sufficient amount to completely react the mixture was added to the mixture and a mortar grinder-mixing step was performed till the ethanol-free condition.
The resulting mixture was initially heat-treated at 400° C. for 5 hours under an atmosphere where dry air was circulating. The first heat-treated mixture was re-mixed to uniformly distribute lithium salts in the mixture. The re-mixed mixture was again heat-treated at 750° C. for 12 hours by increasing temperature at a rate of 3° C./min. At this time, the first and the second heat-treating temperatures were maintained for a predetermined time and then the mixture was cooled. As a result, crystalline LiCoO2 powder was obtained. This LiCoO2 powder had secondary particles with a size of about 10 μm. The secondary particle was prepared by gathering primary particles with a size of 1 μm.
The LiCoO2 powder was dipped into a Mg-methoxide solution for about 10 minutes and the dipped LiCoO2 powder was separated from the solution. The dipped LiCoO2 powder was then dried at 120° C. for about 5 hours in an oven to thereby prepare a Mg-methoxide coated LiCoO2 powder. Then, the Mg-methoxide coated LiCoO2 powder was heat-treated at 600° C. for about 10 hours under an atmosphere where dry air was circulating to thereby prepare a Mg oxide-coated active material.
Then, the active material was mixed with Super P carbon as a conductive agent, KF-1300 polyvinylidenefluoride as a binder and N-methylpyrrolidone as a solvent to prepare an active material slurry. The slurry was cast into a tape shape to act as a positive electrode. The positive electrode was then assembled with a lithium metal foil for a counter electrode by using a lithium salt solution for an electrolyte to thereby fabricate a coin cell-type half-cell. The lithium salt solution included a 1:1 volume ratio of ethylene carbonate and dimethyl carbonate as a solvent and 1M LiPF6 as a solute.
EXAMPLE 2
A positive electrode was prepared in the same way as in Example 1 with the exception that the Mg-methoxide coated LiCoO2 powder was heat-treated at 700° C. A coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
COMPARATIVE EXAMPLE 1
A positive electrode was prepared in the same way as in Example 1 its with the exception that LiCoO2 powder (commercially available from Nippon Chemical under the trade name NC-10) was dipped into a Mg-methoxide solution. The LiCoO2 powder included smooth surfaced mono particles of a 10 μm size. A coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
COMPARATIVE EXAMPLE 2
A positive electrode was prepared in the same way as in Comparative Example 1 with the exception that the Mg-methoxide coated LiCoO2 powder was heat-treated at 700° C. A coin-type half-cell was fabricated with the resulting positive electrode in combination with other components as described in Example 1.
FIG. 1 is a SEM photograph of the LiCoO2 powder used in Examples 1 or 2, and FIG. 2 is a SEM photograph of the LiCoO2 powder used in Comparative Examples 1 or 2. As shown in FIG. 1, the LiCoO2 powder used in Examples 1 or 2 included secondary particles with a size of about 10 μm. The secondary particle was gathered with primary particles with a size of 1 μm. As shown in FIG. 2, the LiCoO2 powder used in Comparative Examples 1 or 2 had smooth surfaced mono particles with a size of 10 μm.
In order to assess the stability of the cells of Example 1 and Comparative Example 1, a DSC analysis performed. The DSC analysis result illustrates the thermal stability properties of the sample. After charging a lithium cell, a structure of a positive active material is converted from LiCoO2 to by Li1-xCoxO2. Because the Li1-xCoxO2 active material is unstable, oxygen boned with metal (Co—O) decomposes according to increases in temperatures. The decomposed oxygen may react with an electrolyte in a cell and causes the cell to explode. Accordingly, the temperature and the quantity of heat evolved when oxygen decomposed significantly effect the stability of the cell.
The cells of Example 1 and Comparative Example 1 were charged by 4.3V and the positive electrode was removed from the cells. In the positive electrodes, LiCoO2 was converted into Li1-xCoO2. The DSC on the electrodes was performed and the results are shown in FIG. 3. In FIG. 3, the DSC analysis result of LiCoO2 used in Comparative Example 1 is indicated by a parenthesized symbol A, and that of LiCoO2 coated with Mg-oxide used in Comparative Example 1 is indicated by another symbol A600. The DSC analysis result of LiCoO2 used in Example 1 is indicated by a parenthesized symbol B, and that of LiCoO2 coated with Mg-oxide used in Example 1 is indicated by another symbol B600. The oxygen decomposition temperature of A600 is lower than A. The result shows that the metallic oxide-coating layer decreases the thermal stability of the LiCoO2 powder having smooth surfaced mono particles. Whereas, the metallic oxide coating layer increases the thermal stability of the LiCoO2 powder having secondary particles with a size of about 10 μm gathered with primary particles with a size of 1 μm. It is also seen that the oxygen decomposition temperature in B600 is higher than B and the quantity of heat evolved is lower than B. These results consider the fact that the structure of the LiCoO2 powder used in Example 1 is different from, Comparative Example 1. Namely, the LiCoO2 used in Example 1 has larger specific surface area than the LiCoO2 used in Comparative Example 1 such that the metallic-oxide,coating effect in Example 1 is different from that in Comparative Example 1.
The DSC analysis also was performed with respect to the position electrode prepared according to Example 2 and Comparative Example 2 and the results are shown in FIG. 4. In FIG. 4, the DSC analysis result of LiCoO2 used in Comparative Example 2 is indicated by a parenthesized symbol A, and that of LiCoO2 coated with Mg-oxide used in Comparative Example 1 is indicated by another symbol A700. The DSC analysis result of LiCoO2 used in Example 2 is indicated by a parenthesized symbol B and that of LiCoO2 coated with Mg-oxide used in Example 2 is indicated by another symbol B700. The result also indicates that the metallic-oxide coating beneficially effects the LiCoO2 in Example 2, as opposed to its effects on the LiCoO2 in Comparative Example 2.
FIG. 5 shows cycle life characteristics of the cells according to Example 2 and Comparative Example 2. The cycle life characteristic of the cell according to Example 2 is indicated by a parenthesized symbol A700 and that of the cell according to Comparative Example 2 is indicated by a parenthesized symbol B700. Further, the cycle life characteristic of the cell which is prepared by the same method in Example 2 (except for using LiCoO2 without the metallic-alkoxide coating operation) is indicated by a parenthesized symbol A. The cycle life characteristic of the cell which is prepared by the same method Comparative example 2 (except for using LiCoO2 without the metallic-alkoxide coating operation) is indicated by a parenthesized symbol B. As shown in FIG. 5, (A700) and (B700) have better cycle life characteristics than (A) and (B). In addition, (A700) has the best cycle life characteristics.
EXAMPLE 3
A positive electrode was prepared in the same way as in Example 1 with the exception that crystalline LiCoF2 powder was prepared by mixing LiOH, Co(OH)2 and LiF. A coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described, in Example 1.
EXAMPLE 4
A positive electrode was prepared in the same way as in Example 1 with the exception that crystalline LiCoS2 powder was prepared by mixing LiOH, Co(OH)2 and NaS. A coin-type half-cell was fabricated with the resulting positive electrode in combination with the other components as described in Example 1.
The SEM result of LiCoF2 and LiCoS2 used in Examples 3 and 4 respectively was similar to Example 1. Accordingly, it is presumed that the LiCoF2 and LiCoS2 powder have secondary particles gathered With primary particles. In addition, the DSC results of LiCoF2 and LiCoS2 with and without a metallic-alkoxide coating operation were similar to Example 1, thus indicating that the thermal stability is improved by the metallic-oxide coating.
As described above, the positive active material of the present invention has been shown to have good thermal and structural safety properties.
While the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art will appreciate that various modifications and substitutions can be made thereto without departing from the spirit and scope of the present invention as set forth in the appended claims.

Claims (4)

What is claimed is:
1. A positive active material for a rechargeable lithium battery, the positive active material comprising:
a cobalt-based compound selected from the group consisting of compounds represented by formulas 1 to 4; and
a metallic oxide coated on the cobalt-based compound;
the positive active material including secondary particles with a size of 10 to 30 μm, the secondary particle being prepared by gathering primary particle with a size of 1 to 5 μm;
LiCoA2  (1)
LiCoO2-xBx  (2)
LiCo1-xMxA2  (3)
LiCo1-xMxO2-yBy  (4)
where A is selected the group consisting of O, S, F and P,
B is selected the group consisting of S, F and P,
M is a transition metal selected from the group consisting of Al, Mg, Cr and Mn; Sr; or lanthanide metal selected from La or Ce;
0<x<1 and 0<y<1.
2. The positive active material of claim 1, wherein the metallic oxide is selected from the group consisting of Mg, Al, Co, K, Na, Ca, Si, Ti and V.
3. A method of preparing a positive active material for a rechargeable lithium battery, comprising the steps of:
obtaining a powder from a source material, the source material being selected from the group consisting of compounds represented by the formulas 1 to 4 and including secondary particles with a size of 10 to 30 μm, the secondary particle being prepared by gathering primary particles with a size of 1 to 5 μm;
coating the powder with a metallic alkoxide solution or a metal aqueous solution to make an metal alkoxide or metal hydrate-coated powder; and
heat-treating the metal alkoxide or metal hydrate-coated powder such that the metallic alkoxide or metal hydrate-coated powder is converted into a metallic oxide-coated powder.
LiCoA2  (1)
LiCoO2-xBx  (2)
LiCo1-xMxA2  (3)
LiCo1-xMxO2-yBy  (4)
where A is selected from the group consisting of O, S, F and P,
B is seeded from the group consisting of S, F and P,
M is a transition metal selected from the group consisting of Al, Mg, Cr and Mn; a transition metal selected from the group consisting of Cr and Mn; Sr; or lanthanide metal selected from La or Ce;
0<x<1 and 0<y<1.
4. The method of claim 3, wherein the heat-treating step is performed at 300 to 800° C. under an air or oxygen atmosphere.
US09/505,389 1999-03-30 2000-02-16 Positive active material for rechargeable lithium batteries and method of preparing same Expired - Lifetime US6756155B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1019990011043A KR100326455B1 (en) 1999-03-30 1999-03-30 Positive active material for lithium secondary battery and method of preparing the same
KR1999-11043 1999-03-30

Publications (1)

Publication Number Publication Date
US6756155B1 true US6756155B1 (en) 2004-06-29

Family

ID=36797643

Family Applications (1)

Application Number Title Priority Date Filing Date
US09/505,389 Expired - Lifetime US6756155B1 (en) 1999-03-30 2000-02-16 Positive active material for rechargeable lithium batteries and method of preparing same

Country Status (3)

Country Link
US (1) US6756155B1 (en)
JP (2) JP3869182B2 (en)
KR (1) KR100326455B1 (en)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020071990A1 (en) * 2000-10-09 2002-06-13 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US20040048158A1 (en) * 2001-12-06 2004-03-11 Masaya Okochi Lithium ion secondary cell
US20040072073A1 (en) * 2001-10-29 2004-04-15 Masaya Okochi Lithium ion secondary battery
US20040121235A1 (en) * 2002-10-01 2004-06-24 Amatucci Glenn G. Metal fluorides as electrode materials
US20040180134A1 (en) * 2000-03-13 2004-09-16 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US20050220701A1 (en) * 2003-03-31 2005-10-06 Seimi Chemical Co., Ltd. Process for producing positive electrode active material for lithium secondary battery
US20050260495A1 (en) * 2004-05-21 2005-11-24 Tiax Llc Lithium metal oxide materials and methods of synthesis and use
US20050271945A1 (en) * 2001-12-19 2005-12-08 Nichia Corporation Positive electrode active material for lithium ion secondary battery
US20060035148A1 (en) * 2002-09-13 2006-02-16 Palani Balaya Novel electrodes for li-based electrochemical energy storage devices and a li-based electrochemical storage device
US20060063070A1 (en) * 2004-09-22 2006-03-23 Takanobu Chiga Positive electrode active material, positive electrode and nonaqueous electrolyte secondary battery
US20080135802A1 (en) * 2005-05-17 2008-06-12 Agc Seimi Chemical Co., Ltd. Process for producing lithium-containing composite oxide for positive electrode of lithium secondary battery
US20090123851A1 (en) * 2007-11-14 2009-05-14 Sony Corporation Positive-electrode active material for lithium-ion secondary battery, positive electrode, manufacturing method thereof, and lithium-ion secondary battery
USRE40834E1 (en) 2001-01-19 2009-07-07 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium batteries and method of preparing the same
US20130196056A1 (en) * 2009-03-23 2013-08-01 Toyo Aluminium Kabushiki Kaisha Electrode structure, capacitor, battery, and method for manufacturing electrode structure
CN103441255A (en) * 2013-09-16 2013-12-11 宁德新能源科技有限公司 Positive pole material of lithium ion battery and preparation method of positive pole material
US20140030559A1 (en) * 2005-10-05 2014-01-30 Rachid Yazami Lithium ion fluoride electrochemical cell
US20140050993A1 (en) * 2012-08-14 2014-02-20 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery, method for preparing same and rechargeable lithium battery including same
US9640793B2 (en) 2012-07-24 2017-05-02 Quantumscape Corporation Nanostructured materials for electrochemical conversion reactions
US10326135B2 (en) 2014-08-15 2019-06-18 Quantumscape Corporation Doped conversion materials for secondary battery cathodes
CN110299555A (en) * 2018-03-22 2019-10-01 绵阳德远英科技有限责任公司 A kind of quick charge lithium ion battery based on anode and electrolyte
US10868309B2 (en) 2016-03-31 2020-12-15 Lg Chem, Ltd. Positive electrode active material particle including core containing lithium cobalt oxide and coating layer containing boron and fluorine, and preparation method thereof
US11183681B2 (en) * 2018-10-25 2021-11-23 Samsung Electronics Co., Ltd. Composite cathode active material, cathode and lithium battery each including the same, and method of preparing composite cathode active material
US11271202B2 (en) 2018-08-22 2022-03-08 Samsung Sdi Co., Ltd. Positive active material, method of manufacturing the same, and positive electrode and rechargeable lithium battery including the same
US11557756B2 (en) 2014-02-25 2023-01-17 Quantumscape Battery, Inc. Hybrid electrodes with both intercalation and conversion materials

Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002289261A (en) * 2001-01-16 2002-10-04 Matsushita Electric Ind Co Ltd Non-aqueous electrolyte secondary battery
KR100696619B1 (en) * 2000-09-25 2007-03-19 삼성에스디아이 주식회사 A positive actvive material for a lithium secondary battery and a method of preparing the same
JP4973825B2 (en) * 2000-11-14 2012-07-11 戸田工業株式会社 Method for producing positive electrode active material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery
US6753112B2 (en) 2000-12-27 2004-06-22 Kabushiki Kaisha Toshiba Positive electrode active material and non-aqueous secondary battery using the same
KR100674015B1 (en) 2001-02-12 2007-01-24 주식회사 엘지화학 Positive active material for lithium secondary battery with higher cycle performance, method for preparing the same, and lithium secondary battery having the same
KR100412523B1 (en) * 2001-08-10 2003-12-31 삼성에스디아이 주식회사 A positive active material for a lithium secondary battery and a lithium secondary battery comprising the same
KR100666821B1 (en) 2004-02-07 2007-01-09 주식회사 엘지화학 Organic/inorganic composite porous layer-coated electrode and electrochemical device comprising the same
WO2006025662A1 (en) 2004-09-02 2006-03-09 Lg Chem, Ltd. Organic/inorganic composite porous film and electrochemical device prepared thereby
KR101153755B1 (en) 2005-09-27 2012-06-13 에이지씨 세이미 케미칼 가부시키가이샤 Process for producing lithium-containing composite oxide for positive electrode of lithium secondary cell
JP4984478B2 (en) * 2005-10-04 2012-07-25 住友化学株式会社 Positive electrode active material and non-aqueous electrolyte secondary battery
KR100805875B1 (en) 2006-12-29 2008-02-20 한양대학교 산학협력단 Olivine type positive active material precursor for lithium battery, and method for preparing the same
KR100966024B1 (en) 2007-04-24 2010-06-24 주식회사 엘지화학 A electrochemical device having a different kind of separators
KR100804085B1 (en) 2007-05-23 2008-02-18 금오공과대학교 산학협력단 A positive active material for a lithium secondary battery and a method of preparing same
KR101430615B1 (en) * 2007-09-19 2014-08-14 삼성에스디아이 주식회사 Cathode and lithium battery using the same
KR100945036B1 (en) 2008-07-31 2010-03-05 한국세라믹기술원 Cathode active material and Preparation method, Lithium secondary battery and Preparation method
KR101013938B1 (en) 2008-07-31 2011-02-14 한양대학교 산학협력단 Positive active material for rechargeable lithium battery, method for preparing same, and rechargeable lithium battery using same
JP5610178B2 (en) * 2008-10-02 2014-10-22 戸田工業株式会社 Lithium composite compound particle powder and method for producing the same, non-aqueous electrolyte secondary battery
KR101050438B1 (en) 2008-11-10 2011-07-19 주식회사 코캄 A positive electrode active material for lithium secondary batteries having excellent safety, a method of manufacturing the same, and a lithium secondary battery comprising the same
JP5149926B2 (en) * 2010-03-05 2013-02-20 株式会社日立製作所 Positive electrode for lithium ion secondary battery, lithium ion secondary battery, vehicle equipped with the same, and power storage system
KR101224618B1 (en) * 2010-03-25 2013-02-19 주식회사 엘앤에프신소재 Positive active material for rechargeable lithium battery, cathod for rechargeable lithium battery, rechargeable lithium battery and method for manufacturing thereof
JP5813972B2 (en) * 2011-03-22 2015-11-17 Ｄｏｗａホールディングス株式会社 Lithium-transition metal composite oxide powder, method for producing the same, and positive electrode active material for all solid lithium battery using the powder
JP5634362B2 (en) * 2011-09-15 2014-12-03 本田技研工業株式会社 Electrode active material and method for producing the same
TWI520422B (en) * 2012-11-26 2016-02-01 財團法人工業技術研究院 Electrode powder and electrode plate for lithium ion battery
JP5741969B2 (en) * 2013-08-05 2015-07-01 戸田工業株式会社 Lithium composite compound particle powder and method for producing the same, non-aqueous electrolyte secondary battery
JP6878855B2 (en) * 2016-11-30 2021-06-02 住友金属鉱山株式会社 Method for manufacturing positive electrode active material for non-aqueous electrolyte secondary batteries
JP7005693B2 (en) * 2020-06-24 2022-01-21 古河機械金属株式会社 Positive electrode active material for lithium-ion batteries, positive electrode materials, positive electrodes, and lithium-ion batteries
CN116075481A (en) * 2020-08-07 2023-05-05 株式会社半导体能源研究所 Secondary battery, vehicle, and method for manufacturing secondary battery

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08153513A (en) 1994-11-29 1996-06-11 Sony Corp Manufacture of positive electrode active material
US6071649A (en) * 1997-10-31 2000-06-06 Motorola, Inc. Method for making a coated electrode material for an electrochemical cell
US20010031397A1 (en) * 2000-02-28 2001-10-18 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US20020031706A1 (en) * 2000-07-31 2002-03-14 Sankar Dasgupta Particulate electrode including electrolyte for a rechargeable lithium battery
US6372385B1 (en) * 1998-02-10 2002-04-16 Samsung Display Devices Co., Ltd. Active material for positive electrode used in lithium secondary battery and method of manufacturing same
US20020055042A1 (en) * 2000-03-13 2002-05-09 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US20020071991A1 (en) * 2000-09-25 2002-06-13 Kweon Ho-Jin Positive active material for rechargeable lithium batteries and method of preparing same
US20020076486A1 (en) * 2000-09-25 2002-06-20 Kweon Ho-Jin Method of preparing positive active material for rechargeable lithium batteries
US20020110736A1 (en) * 2000-09-25 2002-08-15 Kweon Ho-Jin Positive active material for rechargeable lithium batteries and method for preparing same
US20030003352A1 (en) * 2001-04-02 2003-01-02 Samsung Sdi Co., Ltd. Positive electrode for rechargeable lithium batteries and method of the same
US6531220B1 (en) * 1999-06-17 2003-03-11 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US20030073004A1 (en) * 2001-10-17 2003-04-17 Samsung Sdi, Co., Ltd. Active material for lithium secondary battery and method of preparing active material

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08153513A (en) 1994-11-29 1996-06-11 Sony Corp Manufacture of positive electrode active material
US6071649A (en) * 1997-10-31 2000-06-06 Motorola, Inc. Method for making a coated electrode material for an electrochemical cell
US6372385B1 (en) * 1998-02-10 2002-04-16 Samsung Display Devices Co., Ltd. Active material for positive electrode used in lithium secondary battery and method of manufacturing same
US20020061444A1 (en) * 1998-02-10 2002-05-23 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US6531220B1 (en) * 1999-06-17 2003-03-11 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US20010031397A1 (en) * 2000-02-28 2001-10-18 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US6653021B2 (en) * 2000-02-28 2003-11-25 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US20020055042A1 (en) * 2000-03-13 2002-05-09 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US20020031706A1 (en) * 2000-07-31 2002-03-14 Sankar Dasgupta Particulate electrode including electrolyte for a rechargeable lithium battery
US20020110736A1 (en) * 2000-09-25 2002-08-15 Kweon Ho-Jin Positive active material for rechargeable lithium batteries and method for preparing same
US20020076486A1 (en) * 2000-09-25 2002-06-20 Kweon Ho-Jin Method of preparing positive active material for rechargeable lithium batteries
US20020071991A1 (en) * 2000-09-25 2002-06-13 Kweon Ho-Jin Positive active material for rechargeable lithium batteries and method of preparing same
US20030003352A1 (en) * 2001-04-02 2003-01-02 Samsung Sdi Co., Ltd. Positive electrode for rechargeable lithium batteries and method of the same
US20030073004A1 (en) * 2001-10-17 2003-04-17 Samsung Sdi, Co., Ltd. Active material for lithium secondary battery and method of preparing active material

Cited By (45)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040180134A1 (en) * 2000-03-13 2004-09-16 Kweon Ho-Jin Positive active material for rechargeable lithium battery and method of preparing same
US6974601B2 (en) * 2000-03-13 2005-12-13 Samsung Sdi Co., Ltd. Method of preparing positive active material for rechargeable lithium battery
US7138209B2 (en) 2000-10-09 2006-11-21 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US20040018429A1 (en) * 2000-10-09 2004-01-29 Samsung Sdi Co, Ltd Positive active material for rechargeable lithium battery and method of preparing same
US20020071990A1 (en) * 2000-10-09 2002-06-13 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US8034486B2 (en) * 2000-10-09 2011-10-11 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
US8007941B2 (en) 2000-10-09 2011-08-30 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery and method of preparing same
USRE40834E1 (en) 2001-01-19 2009-07-07 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium batteries and method of preparing the same
US20040072073A1 (en) * 2001-10-29 2004-04-15 Masaya Okochi Lithium ion secondary battery
US7150940B2 (en) * 2001-10-29 2006-12-19 Matsushita Electric Industrial Co., Ltd. Lithium ion secondary battery
US20040048158A1 (en) * 2001-12-06 2004-03-11 Masaya Okochi Lithium ion secondary cell
US7179565B2 (en) * 2001-12-06 2007-02-20 Matsushita Electric Industrial Co., Ltd. Lithium ion secondary cell
US20060093549A1 (en) * 2001-12-19 2006-05-04 Nichia Corporation Positive electrode active material for lithium ion secondary battery
US7459238B2 (en) 2001-12-19 2008-12-02 Nichia Corporation Positive electrode active material for lithium ion secondary battery
US20050271945A1 (en) * 2001-12-19 2005-12-08 Nichia Corporation Positive electrode active material for lithium ion secondary battery
US20060035148A1 (en) * 2002-09-13 2006-02-16 Palani Balaya Novel electrodes for li-based electrochemical energy storage devices and a li-based electrochemical storage device
US20040121235A1 (en) * 2002-10-01 2004-06-24 Amatucci Glenn G. Metal fluorides as electrode materials
US7371338B2 (en) * 2002-10-01 2008-05-13 Rutgers, The State University Metal fluorides as electrode materials
US20050220701A1 (en) * 2003-03-31 2005-10-06 Seimi Chemical Co., Ltd. Process for producing positive electrode active material for lithium secondary battery
US7270797B2 (en) * 2003-03-31 2007-09-18 Seimi Chemical Co., Ltd. Process for producing positive electrode active material for lithium secondary battery
US20080286460A1 (en) * 2004-05-21 2008-11-20 Tiax Llc Lithium metal oxide materials and methods of synthesis and use
US7381496B2 (en) 2004-05-21 2008-06-03 Tiax Llc Lithium metal oxide materials and methods of synthesis and use
US20050260495A1 (en) * 2004-05-21 2005-11-24 Tiax Llc Lithium metal oxide materials and methods of synthesis and use
US20060063070A1 (en) * 2004-09-22 2006-03-23 Takanobu Chiga Positive electrode active material, positive electrode and nonaqueous electrolyte secondary battery
US20080135802A1 (en) * 2005-05-17 2008-06-12 Agc Seimi Chemical Co., Ltd. Process for producing lithium-containing composite oxide for positive electrode of lithium secondary battery
US8163198B2 (en) * 2005-05-17 2012-04-24 Agc Seimi Chemical Co., Ltd. Process for producing lithium-containing composite oxide for positive electrode of lithium secondary battery
US20140030559A1 (en) * 2005-10-05 2014-01-30 Rachid Yazami Lithium ion fluoride electrochemical cell
US20090123851A1 (en) * 2007-11-14 2009-05-14 Sony Corporation Positive-electrode active material for lithium-ion secondary battery, positive electrode, manufacturing method thereof, and lithium-ion secondary battery
US8178238B2 (en) * 2007-11-14 2012-05-15 Sony Corporation Positive-electrode active material for lithium-ion secondary battery, positive electrode, manufacturing method thereof, and lithium-ion secondary battery
US8976509B2 (en) 2009-03-23 2015-03-10 Toyo Aluminium Kabushiki Kaisha Aluminum material
US20130196056A1 (en) * 2009-03-23 2013-08-01 Toyo Aluminium Kabushiki Kaisha Electrode structure, capacitor, battery, and method for manufacturing electrode structure
US8638545B2 (en) * 2009-03-23 2014-01-28 Toyo Aluminium Kabushiki Kaisha Electrode structure, capacitor, battery, and method for manufacturing electrode structure
US10511012B2 (en) 2012-07-24 2019-12-17 Quantumscape Corporation Protective coatings for conversion material cathodes
US9640793B2 (en) 2012-07-24 2017-05-02 Quantumscape Corporation Nanostructured materials for electrochemical conversion reactions
US9692039B2 (en) 2012-07-24 2017-06-27 Quantumscape Corporation Nanostructured materials for electrochemical conversion reactions
US20140050993A1 (en) * 2012-08-14 2014-02-20 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery, method for preparing same and rechargeable lithium battery including same
US9614225B2 (en) * 2012-08-14 2017-04-04 Samsung Sdi Co., Ltd. Positive active material for rechargeable lithium battery, method for preparing same and rechargeable lithium battery including same
CN103441255B (en) * 2013-09-16 2017-02-01 宁德新能源科技有限公司 Positive pole material of lithium ion battery and preparation method of positive pole material
CN103441255A (en) * 2013-09-16 2013-12-11 宁德新能源科技有限公司 Positive pole material of lithium ion battery and preparation method of positive pole material
US11557756B2 (en) 2014-02-25 2023-01-17 Quantumscape Battery, Inc. Hybrid electrodes with both intercalation and conversion materials
US10326135B2 (en) 2014-08-15 2019-06-18 Quantumscape Corporation Doped conversion materials for secondary battery cathodes
US10868309B2 (en) 2016-03-31 2020-12-15 Lg Chem, Ltd. Positive electrode active material particle including core containing lithium cobalt oxide and coating layer containing boron and fluorine, and preparation method thereof
CN110299555A (en) * 2018-03-22 2019-10-01 绵阳德远英科技有限责任公司 A kind of quick charge lithium ion battery based on anode and electrolyte
US11271202B2 (en) 2018-08-22 2022-03-08 Samsung Sdi Co., Ltd. Positive active material, method of manufacturing the same, and positive electrode and rechargeable lithium battery including the same
US11183681B2 (en) * 2018-10-25 2021-11-23 Samsung Electronics Co., Ltd. Composite cathode active material, cathode and lithium battery each including the same, and method of preparing composite cathode active material

Also Published As

Publication number Publication date
JP3869182B2 (en) 2007-01-17
JP2006190687A (en) 2006-07-20
JP4361060B2 (en) 2009-11-11
JP2000306584A (en) 2000-11-02
KR100326455B1 (en) 2002-02-28
KR20000061755A (en) 2000-10-25

Similar Documents

Publication Publication Date Title
US6756155B1 (en) Positive active material for rechargeable lithium batteries and method of preparing same
US6531220B1 (en) Positive active material for rechargeable lithium battery and method of preparing same
US6753111B2 (en) Positive active material for rechargeable lithium batteries and method for preparing same
JP4973825B2 (en) Method for producing positive electrode active material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery
JP5753650B2 (en) Positive electrode active material for lithium secondary battery and method for producing the same
US7655358B2 (en) Positive active material composition for rechargeable lithium battery and method of preparing positive electrode using same
JP4574877B2 (en) Positive electrode active material for lithium secondary battery and method for producing the same
JP4362021B2 (en) Positive electrode active material for lithium secondary battery
JP5879761B2 (en) Lithium composite compound particle powder, method for producing the same, and nonaqueous electrolyte secondary battery
JP3994238B2 (en) Nonaqueous electrolyte lithium secondary battery
JP5731276B2 (en) Positive electrode active material for lithium secondary battery, method for producing the same, and lithium secondary battery
JP2015015244A (en) Positive electrode active material for lithium secondary batteries, method for manufacturing the same, positive electrode for lithium secondary batteries including the same, and lithium secondary battery
KR101904896B1 (en) Positive active material for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same
JP2013503449A (en) Cathode material for lithium batteries coated with metal oxide
EP1497876A1 (en) Complex lithium metal oxides with enhanced cycle life and safety and a process for preparation thereof
KR20030008704A (en) An active material for a battery and a method of preparing the same
KR20160059781A (en) Positive active material for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same
JP6621131B2 (en) Positive electrode active material for lithium secondary battery, method for producing the same, and lithium secondary battery including the same
JP4777543B2 (en) Method for producing lithium cobalt composite oxide
KR100490613B1 (en) A positive active material for a lithium secondary battery and a method of preparing the same
JP2002151078A (en) Positive electrode active material for non-aqueous electrolyte secondary battery and its manufacturing process
EP2824074B1 (en) Positive active material for rechargeable lithium battery and rechargeable lithium battery including the same
JP4553095B2 (en) Cobalt oxide particle powder and production method thereof, positive electrode active material for non-aqueous electrolyte secondary battery, production method thereof, and non-aqueous electrolyte secondary battery
KR20150004648A (en) Positive electrode for rechargeable lithium battery and rechargeable lithium battery including the same
KR20130022018A (en) Positive active material for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same

Legal Events

Date Code Title Description
AS Assignment

Owner name: SAMSUNG SDI CO., LTD., KOREA, REPUBLIC OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KWEON, HO-JIN;KIM, SEUNG-KEE;HWANG, SANG-MOON;AND OTHERS;REEL/FRAME:010615/0613

Effective date: 20000125

STCF Information on status: patent grant

Free format text: PATENTED CASE

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 4

FEPP Fee payment procedure

Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 8

FPAY Fee payment

Year of fee payment: 12